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Name

Motion

Before You Read

Before you read the chapter, respond to these statements. 1. Write an A if you agree with the statement. 2. Write a D if you disagree with the statement.

Before You Read

Motion

? Distance and displacement are the same thing.

? Velocity and speed are the same.

? Whenever an object accelerates, its speed increases.

Date

Construct the Foldable as directed at the beginning of this chapter.

Science Journal

Write a paragraph descibing three rides in an amusement park and how rides cause you to move.

Copyright ? Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Motion 17

Name

Date

Motion

Section 1 Describing Motion

Copyright ? Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Skim Section 1 of the chapter. Read the headings and illustration captions. Write three questions that come to mind. 1. 2. 3.

Review Vocabulary Define meter to reflect its scientific meaning.

meter the SI unit of length, abbreviated m

New Vocabulary Use your book to define the words below.

motion a change in an object's position relative to a reference point distance how far an object travels along its path displacement the distance and direction of an object's change in position from

the starting point speed the distance an object travels per unit of time

average speed instantaneous speed

Contrast the average speed and the instantaneous speed of a runner in a race. The runner's average speed is a single number, the total distance divided by the time the runner took. The instantaneous speed is how fast the runner is moving at any given moment. The instantaneous speed is probably different in different parts of the race.

Academic Vocabulary Use a dictionary to define position with its scientific meaning.

position the location of an object in relation to a reference point

18 Motion

Name Section 1 Describing Motion (continued)

Date

Motion and Position

I found this information

on page

.

SE, pp. 45?46

RE, p. 26

Draw a winding path that covers a distance of 70 miles and finishes with a displacement 20 miles southwest of the starting point. Label your diagram with the distance and direction traveled.

It is easier to see distance and direction on graph paper. Accept all reasonable responses.

Copyright ? Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Speed

I found this information

on page

.

SE, pp. 46?49

RE, pp. 27?28

Analyze the formula for speed by looking at the diagram and filling in the prompts.

Put your finger over the s on the diagram. Now write the formula

for speed. s dt

d

s t

Put your finger over the d on the diagram. Write the calculation to

find distance when you know speed and time. d st

Prove to yourself that these formulas are correct by checking the units.

speed

(units

of

km h

or

m) s

disttaimncee(( uunnititssooff hk mor osr) m)

distance (units of km ) speed (units of khm) time (units of h )

Note that the units always turn out the same on both sides of the equation. Accept reasonable variations on units.

Motion 19

Distance (m) Copyright ? Glencoe/McGraw-Hill, a division of The McGraw-Hill Companies, Inc.

Name Section 1 Describing Motion (continued)

Date

Graphing Motion

I found this information

on page

.

SE, pp. 49?50

RE, p. 29

Create a graph to show the progress of a runner who runs a 1-kilometer race in 3 minutes. The runner gets off to a fast start, runs the middle of the race at a more moderate pace, and then sprints to the finish.

1,000

Graphing Motion

Graphing Checklist:

? title

? scale on x-axis

? units on x-axis

500

? label on x-axis

? scale on y-axis

? units on y-axis

1

2

Time (min)

3

? label on y-axis

ANALYZE IT Analyze the following statement. "A boat traveled at 10 km/h for one hour, then at 13 km/h for two hours, and finally at 11 km/h for another hour. The average speed over the whole trip was 15 km/h." Support your analysis with a calculation. The statement is not reasonable. The average speed has to be somewhere in the middle

of the speeds given. It is impossible to have an average speed higher than the

individual speeds. If the numbers for each part of the trip are correct, the overall distance

covered must be (10 1) (13 2) (11 1) 47 kilometers in four hours, for an

average speed of 47/4 11.75 km/h, not 15 km/h.

20 Motion

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